11 degree forcing cone

[monge]

I have heard talk of cutting ruger forcing cones to 11 degrees for better accuracy with cast what do you guys think? Thanks JOE

[Outpost75]

11 degrees is also what was used in the Colt Python, and is used by many custom gunsmiths.

One advantage of the shallower 11 degree included angle is that a rough or eroded 18 degree cone, as often found on S&Ws, can be cleaned up without enlarging the major diameter of the forcing cone entrance, and without having to set the barrel back.

[monge]

I cut the barrel step on my 44sp vaquero to close up cyl gap, cone is a little shorter now thinking about recutting it . Shoots not bad now I wonder if it would improve accuracy?

[str8shot426]

Most Rugers I have seen come with a 5° forcing cone. Ideally the forcing cone entrance will be .020" over bullet/boolit diameter.

Recutting the original 5° to 11° will open up the entrance over size and create two angles in the forcing cone.

An 11° forcing cone can be cut. But barrel setback is required.

[Outpost75]

When did Ruger change to the 5° cone? I was not aware of that. Jim Clarke and Bill Davis both used the 5° in their custom PPC guns built in Rugers, and they shot wadcutters like a house on fire!

[ClemY]

I used to use an 11 degree cutter when I cleaned up forcing cones. I started using a 5 degree cutter on .357s because an 11 would have produced a step. I have since switched to 5 degrees for everything. I have been pretty happy with the results, but your mileage may vary.

[str8shot426]

Why is that?
Would it not be better if the cone entrance were the same or a few thousandths of an inch as the cylinder throats are?
Why let the bullet go unsupported for longer then it has to?

The .020 oversize is to cover any misalignment of the cylinder to the barrel. Even if the revolver was perfectly aligned it would wear and become out of alignment with normal shooting.
Also, if the start of the forcing cone was the same size as the cylinder throats, there would be no forcing cone at all.

[monge]

So is a shallow cone better or worse?

[ClemY]

So is a shallow cone better or worse?

It probably depends on how your gun shoots. If it is shallow and things work fine, then I wouldn't be inclined to mess with it. Typically I cut them a little deeper, partly to account for chamber misalignment, partly because the factory forcing cone can be a bit rough and I prefer them smoother. While I am getting them smoother, they are getting deeper. Because I prefer the 5 degree cutter, if only because I can't find a 7 or 8 degree cutter, I am typically cleaning up the sometimes steeper forcing cone.

[detox]

Most Rugers I have seen come with a 5° forcing cone. Ideally the forcing cone entrance will be .020" over bullet/boolit diameter.

Recutting the original 5° to 11° will open up the entrance over size and create two angles in the forcing cone.

An 11° forcing cone can be cut. But barrel setback is required.

I hear the Ruger 357 Revolvers are only ones that come with 5 degree cone. My 45 LC Blackhawk is cut at 10-11 degrees from factory.

Lots of pistols are cut well over Brownell's .020" maximum and shoot better or just as good as before.